Semiconductor memory devices have become more popular for use in various electronic devices. For example, non-volatile semiconductor memory is used in cellular telephones, digital cameras, personal digital assistants, mobile computing devices, non-mobile computing devices and other devices. Electrical Erasable Programmable Read Only Memory (EEPROM) and flash memory are among the most popular non-volatile semiconductor memories.
Some semiconductor memory systems generate non-mission critical information in order to help debug problems and understand usage to provide for more efficient operation. Non-mission critical information is data which is not required for normal device operation. Example of non-mission critical information include log information captured during operation of a memory system, device usage trends, statistical information and other information not used for direct system operation. The log information is typically captured by firmware running on the Controller, is used to diagnose failure conditions and other issues, and (in some embodiments) can include error information, temperature variances, error correction activity and other system activity. User data is not non-mission critical information.
Because there is a desire to deliver as much memory capacity to the end user, system designers are reluctant to make portions of the memory available for storing non-mission critical information